This description relates to measuring an amount of charge remaining in a battery.
A battery is typically used as a power source for various portable electronic devices, such as a portable phone, a portable digital assistant (PDA) device, a notebook computer, a portable game player, a digital camera, an MP3 player, and/or a portable multimedia player (PMP).
In the case of a rechargeable battery, the rechargeable battery may be damaged or the life span thereof may be reduced if the battery is excessively recharged or discharged. In order to determine the amount of available charge, an amount of charge in a battery is often measured according to a battery gauge integrated circuit chip or voltage measurement technique. Specifically, a first technique for measuring an amount of charge in a battery includes measuring an amount of charge in a battery using a battery gauge integrated circuit (IC) chip. A second technique for measuring an amount of charge in a battery is based on only a voltage of the battery. The method for measuring an amount of charge in a battery using a battery gauge IC chip allows for the measurement of an amount of charge in a battery based on several conditions, such as the change of a chemical characteristic in a battery, as well as the size, the current, and the voltage of the battery. Although the battery gauge IC chip technique provides accurate and reliable measurement of an amount of charge in a battery, the gauge IC chip used for measurement and/or display may be relatively expensive. In contrast, although the measurement technique based on a voltage of a battery may not be as reliable or accurate as the battery gauge IC chip technique, the circuitry for performing the voltage measurement technique is relatively inexpensive.